Leading Work-Related Diseases and Injuries

The National Institute for Occupational Safety and Health
(NIOSH)
has developed a suggested list of 10 leading work-related diseases
and
injuries and has described the first nine categories on that list.*
A
discussion of the tenth and final category, Psychological
Disorders,
appears below.
PSYCHOLOGICAL DISORDERS

There is increasing evidence that an unsatisfactory work
environment may contribute to psychological disorders. Studies
have
shown that factors contributing to an unsatisfactory work
environment
may include work overload, lack of control over one's work,
nonsupportive supervisors or co-workers, limited job opportunities,
role ambiguity or conflict, rotating shiftwork, and machine-paced
work
(1-4). Psychological disorders that can result from such factors
may
be classified as a) affective disturbances (e.g., anxiety,
irritability), b) behavioral problems (e.g., substance abuse, sleep
difficulties), c) psychiatric disorders (e.g., neuroses), and d)
somatic complaints (e.g., headache, gastrointestinal symptoms). In
addition to psychological disorders, stressful working conditions
may
have a systemic influence, possibly affecting the etiology and/or
prognosis of other disease states, as suggested by recent studies
of
stress-related immunologic suppression (5).

Although data bases currently available for determining the
extent
of work-related psychological disorders are limited, several
indicators suggest that these problems impose substantial health
and
financial costs in the United States. A recent study in California
showed that claims for the development of "work-related neuroses"
more
than doubled during 1980-1982; claims for all other disabling
work-related injuries during the same period actually decreased by
about one-tenth (6). A study of representative medical claims
throughout the country showed that during 1980-1982 claims for
"mental
stress" that developed gradually (i.e., a chronic problem unrelated
to
a single traumatic incident or to any physical work-related
disorder)
accounted for about 11% of all occupational disease claims (7).
Average medical costs and indemnity payments in 1981-1982 for these
forms of mental stress actually surpassed the average amounts for
other occupational diseases (7). The American Psychiatric
Association
now lists occupational stress in its Diagnostic and Statistical
Manual
as a subcategory of the major diagnostic axis of "psychosocial
stress"
(8).

There are increasing data on the relationship between specific
working conditions and psychological disorders. For example, in a
questionnaire survey of over 2,000 workers in 23 different
occupations, strong occupational differences were found in
psychosocial job stressors and in somatic and affective complaints
(1). Ratings of boring, repetitive job tasks and role ambiguity
were
more prominent among several classes of blue-collar workers (e.g.,
assembly-line workers, fork-lift truck drivers, and machine
operators)
than among white-collar professionals (e.g., professors and family
physicians). The most satisfied occupational groups were
physicians,
professors, and white-collar supervisors. Groups experiencing the
highest levels of job stressors and their resultant ill effects
were
assemblers and relief workers on machine-paced assembly lines.

NIOSH investigators ranked 130 occupations by rate of admission
to
community mental health centers in Tennessee to determine the
relative
risk of psychological or stress-related disorders by occupation
(9).
Heading the list were jobs in health care, service occupations, and
blue-collar factory work--which tend to be characterized by
stress-producing conditions such as a lack of control over the job
by
the worker, repetitive work, shift work, and a responsibility for
others.** In other studies, workers on night and rotating shifts
(including the health-care occupations) reported more disturbances
of
sleep; altered eating habits; and higher rates of visits to
clinics,
absences due to sickness, and on-the-job injuries than did those on
fixed day shifts (10-12).

Work environments characterized by technological innovation
have
also been investigated; a major focus has been on office work
influenced by the introduction of computers (13,14). "Adverse
working
conditions" (e.g., poorer physical environment, reduced job control
and social support) tend to be reported more frequently by workers
using new-technology office equipment such as video display
terminals. Some of these conditions have been linked to chronic
stress-related disorders (4,15).

Worksite studies by NIOSH have revealed that job stresses may
contribute to acute disturbances among groups of workers, including
those termed "mass psychogenic illness" (16). The sudden
appearance
of symptoms, usually in response to some "trigger factor" such as a
strange odor, may result in spread of the apparent "illness"
throughout the plant, with symptoms such as headaches, dizziness,
and
nausea. Investigations often fail to detect specific physical or
chemical causative agents. However, factors such as heavy work
load,
strained labor/management relations, and physical discomfort at
work
may be present and related to the reporting of symptoms.

Emerging trends in technology, the economy, and demographic
characteristics of the work force may lead to increased risk for
psychological disorders. For example, a 26% increase is projected
for
employment in the health services, an area that may be associated
with
elevated risk (9, 17). Computers and robots are expected to affect
seven million factory jobs and 39 million office jobs (18).
According
to some forecasters (18), possible consequences may include job
displacement, reduced skill requirements, and lower-paying jobs.
It
has been projected that in the next decade, nine of every 10 new
jobs
will be in the service sector (19). Routine service jobs may not
provide the compensation and benefits associated with the more
traditional industrial and manufacturing jobs (18). Six of 10 new
jobs in the next decade will be filled by women (19), and dual
job/home role demands and constrained occupational opportunities
for
women may result in an adverse impact on their mental health.
Reported by Div of Biomedical and Behavioral Science, National
Institute for Occupational Safety and Health, CDC.

Editorial Note

Editorial Note: A prevention strategy for psychological disorders
should take into account both the causal mechanisms and the factors
that perpetuate these disorders. Work-related psychological
disturbances are known to be influenced by both the physical and
psychosocial characteristics of given job situations. Moreover,
these
factors operate in concert with factors unrelated to the job--such
as
life events; familial demands and support; and the traits,
capacities,
and needs of the workers themselves (e.g., personality, age, sex,
experience/learning). The interaction of these variables is
complex,
and the relative influence of each is not thoroughly understood.
Nevertheless, approaches to prevent work-related psychological
disorders should still be taken using the information currently
available.

Stress-reduction techniques (e.g., meditation, biofeedback,
muscle
relaxation, cognitive restructuring, and anxiety management) have
been
taught to both blue- and white-collar workers in worksite training
sessions. Follow-up studies have shown decreases in
psychophysiologic
activity (e.g., muscle tension and blood pressure levels) and
reductions in subjective reports of anxiety, sleep disturbances,
and
other health complaints with each technique (20). However,
improvement in all these parameters persisted less than 3 months
after
training ended.

Stress management treats only the symptoms of the problem--not
the
cause. Therefore, efforts to control risk factors at the worksite
are
also important. Some previously described suggestions for
controlling
worksite risk factors for psychological disorders are listed below
(21). These suggestions appear to have merit for reducing
work-related psychological disorders, but further evaluation and
study
are needed for a complete understanding of their impact.

Work schedule. Design work schedules to avoid conflict with
demands and responsibilities unrelated to the job. Schedules
for
rotating shifts should be stable and predictable, with rotation
in
a forward (day-to-night) direction.

Participation/control. Allow workers to provide input for
decisions or actions affecting their jobs.

Workload. Ensure assignments are compatible with the
capabilities
and resources of the worker, and allow for recovery from
especially demanding physical or mental tasks.

Content. Design tasks to provide meaning, stimulation, a sense
of
completeness, and an opportunity to use skills.

Roles. Define work roles and responsibilities clearly.

Social environment. Provide opportunities for social
interaction,
including emotional support and help directly related to one's
job.

Future. Avoid ambiguity in matters of job security and career
development.
In addition to evaluation of these suggested actions, efforts
are
needed to advance the understanding of work-related psychological
disorders and of methods appropriate for their control, including:

Improving the systems for surveillance of psychological
disorders
in the workforce as related to working conditions.

Improving research techniques for investigating stressful
working
conditions and their health consequences.

Improving training of occupational health professionals and
workers
in recognizing stressful workplace conditions and signs of
worker
stress and in effecting remedial measures.

Furthering the development of mental health components in
occupational health and safety programs.

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